Anti-interference miniature interface circuit for infrared focal plane detector

Abstract

The invention discloses an anti-interference miniature interface circuit for an infrared focal plane detector, which relates to an infrared focal plane detector and comprises a detector interface, a signal input conditioning circuit, a signal differential output conversion circuit and a miniature interface which are connected in sequence, outputting a detector signal to a micro interface through the signal differential output conversion circuit, wherein the detector interface is used for accessing a detector; the bias voltage circuit comprises a fixed bias voltage part and an adjustable bias voltage part, the fixed bias voltage is connected to a working power supply, and the adjustable bias voltage is completed based on a voltage reference circuit chip and an operational amplifier and used for providing low-noise bias voltage for the detector interface; and the time sequence level conversion circuit is connected between the micro interface circuit and the detector and is used for outputting a time sequence signal provided by an external system to an interface circuit of the detector through a level conversion chip. Various interferences such as electromagnetism can be effectively suppressed, back-end signal processing and transmission are facilitated, and universality is achieved.

Description

Technical Field

[0001] This application relates to the field of infrared focal plane detector technology, and in particular to an anti-interference miniature interface circuit for infrared focal plane detectors. Background Technology

[0002] The interface circuit of an infrared focal plane detector serves as a bridge connecting the detector to the system signal processing board. It provides the infrared detector with power supply voltage and various drive biases, conditions the detector's signal output, and utilizes general-purpose infrared detector acquisition equipment or the detector's application-side signal processing system to achieve photoelectric signal readout and processing. The required drive voltage for the detector is highly sensitive to noise, and the detector's output signal is weak, making it prone to noise and external interference during operation. Therefore, the reliability and stability of the interface circuit are crucial to the detector's performance and largely determine its overall performance level.

[0003] Traditional infrared focal plane detector interface circuit driving methods, in order to better control noise and facilitate design, often involve relatively large interface circuit sizes and connection methods that occupy considerable space. Furthermore, the detector signal output is directly output after operational amplifier gain adjustment, making the output signal susceptible to interference during transmission, resulting in significant noise and greatly reducing the detector's performance. This approach is unsuitable for infrared focal plane detector interface circuits that require precise interface circuit size and installation dimensions, low-noise signal output, and strong anti-interference capabilities. Therefore, it is essential to develop infrared focal plane detector interface circuits that are low-noise, have small structural and installation space requirements, and possess strong anti-interference capabilities. Summary of the Invention

[0004] This application provides an anti-interference miniature interface circuit for an infrared focal plane detector. Through the cooperation of a signal input conditioning unit and a signal differential output conversion circuit, the anti-interference capability of the detector signal output is enhanced, effectively suppressing various interferences such as electromagnetic interference, and facilitating back-end signal processing and transmission.

[0005] This application provides an anti-interference miniature interface circuit for an infrared focal plane detector, comprising: a detector interface, a signal input conditioning circuit, a signal differential output conversion circuit, a bias voltage circuit, a timing level conversion circuit, and a miniature interface circuit, wherein: The detector interface, the signal input conditioning circuit, the signal differential output conversion circuit, and the miniature interface circuit are connected in sequence. The detector signal is input to the signal conditioning circuit, and the detector signal is output to the miniature interface circuit through the signal differential output conversion circuit. The detector interface is used to connect the detector. The bias voltage circuit comprises two parts: a fixed bias voltage and an adjustable bias voltage. The fixed bias voltage is connected to the operating power supply, while the adjustable bias voltage is based on a voltage reference circuit chip and an operational amplifier, and is used to provide a low-noise bias voltage for the detector interface. The timing level conversion circuit is connected between the miniature interface circuit and the detector, and is used to output the timing signal provided by the external system through the level conversion chip to the interface circuit of the detector.

[0006] Optionally, the detector interface is a tiny rectangular connector that connects to the detector's electrical interface. The micro interface circuit includes multiple micro socket terminals, which respectively realize input and output according to the definition.

[0007] Optionally, it also includes a constant current driving circuit for a temperature-sensing diode, wherein the constant current driving circuit for a temperature-sensing diode receives the temperature measurement signal input from the detector interface and outputs it to the micro interface circuit. The constant current drive circuit for the temperature-sensing diode is implemented using resistors, diodes, and operational amplifiers, and is used to provide a stable drive current for the temperature-sensing diode inside the detector.

[0008] Optionally, the signal input conditioning circuit includes: a differential operational amplifier N1A; The non-inverting input terminal of the differential operational amplifier is connected to the detector signal input through resistor R0, and to the VF signal input through resistor R1; The inverting input of the differential operational amplifier is connected to its output via resistor R7.

[0009] Optionally, the signal differential output conversion circuit includes: a fully differential input / output amplifier N2 and a differential operational amplifier N1B; The output signal of the differential operational amplifier N1A is connected to the first input terminal of the fully differential input / output amplifier N2 through resistor R18, and the output signal of the differential operational amplifier N1A is also connected to its first output terminal through a series connection of resistor R18 and resistor R14. The differential operational amplifier N1B has its non-inverting input terminal connected to the reference voltage through resistor R2, and its non-inverting input terminal is also connected to ground through resistor R2 and capacitor C7 in parallel. The inverting input terminal of the differential operational amplifier N1B is connected to its output terminal through resistor R8. The output terminal of the differential operational amplifier N1B is connected to the second input terminal of the fully differential input / output amplifier N2 through resistor R19. The output terminal of the differential operational amplifier N1B is connected to the second output terminal of the fully differential input / output amplifier N2 through a series connection of resistor R19 and resistor R15. The fully differential input / output amplifier N2 converts the detector signal into two differential signals through its first and second output terminals.

[0010] Optionally, the fixed bias section of the bias voltage circuit is implemented based on a series connection of a resistor and a capacitor; The adjustable bias section of the bias voltage circuit includes a voltage reference circuit chip N5 and an operational amplifier N4C. The input terminal of the voltage reference circuit chip N5 is connected to VCC, and the output terminal is connected to the non-inverting input terminal of the operational amplifier N4C through resistor R26. The output terminal of the voltage reference circuit chip N5 is grounded through the series connection of resistors R26 and R27, and the non-inverting input terminal of the operational amplifier N4C is grounded through the parallel connection of resistor R27 and capacitor C10. The inverting input terminal of the operational amplifier N4C is connected to its output terminal through capacitor C21. The output terminal of the operational amplifier N4C is connected to VP1 through resistor R13. The inverting input terminal of the operational amplifier N4C is connected to VP1 through resistor R30. VP1 is grounded through capacitor C14.

[0011] Optionally, the constant current drive circuit for the temperature sensing diode includes an amplifier N6; The non-inverting input terminal of the amplifier N6 is connected to the positive terminal DTK of the internal temperature sensing diode of the detector, and VCC is connected to the non-inverting input terminal of the amplifier N6 through resistor R37. The output terminal of amplifier N6 outputs a measurement signal V-DTK, and the output terminal of amplifier N6 is grounded through resistors R38 and R39; The inverting input of amplifier N6 is connected between resistors R38 and R39.

[0012] Optionally, the timing level conversion circuit includes outputting the digital signals required for the operation of the MC and INT detectors through level conversion and resistors.

[0013] Optionally, the micro interface circuit is a tiny rectangular through-hole socket with a specified number of pins.

[0014] This application embodiment enhances the anti-interference capability of the detector signal output through the cooperation of the signal input conditioning unit and the signal differential output conversion circuit. It effectively suppresses various interferences, including electromagnetic interference, facilitating backend signal processing and transmission. The low-noise, high-precision bias voltage circuit provides the required bias voltage and operating power for low-noise, high-precision, adjustable, and highly stable multi-channel detectors. The device is small in size, saves space through cascading, and features strong anti-interference capability and easy transmission of the detector output signal. It is highly versatile, adaptable to different types and specifications of analog signal output detectors, and easy to adjust. It offers high cost-effectiveness, ease of operation, and significant engineering value, especially for applications with high space requirements.

[0015] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0016] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of the basic architecture of an anti-interference miniature interface circuit for an infrared focal plane detector according to an embodiment of this application. Figure 2 This is a schematic diagram of the signal input conditioning circuit for an anti-interference miniature interface circuit for an infrared focal plane detector according to an embodiment of this application. Figure 3 This is a schematic diagram of the signal differential output conversion circuit for an anti-interference miniature interface circuit for an infrared focal plane detector according to an embodiment of this application. Figure 4 This is a schematic diagram of the bias voltage circuit for an anti-interference miniature interface circuit for an infrared focal plane detector according to an embodiment of this application. Figure 5 This is a schematic diagram of a temperature-sensing diode constant current drive circuit for an anti-interference miniature interface circuit for an infrared focal plane detector according to an embodiment of this application. Figure 6 This is a schematic diagram of the timing level conversion circuit of the anti-interference miniature interface circuit for an infrared focal plane detector according to an embodiment of this application. Figure 7 This is a schematic diagram of a miniature input / output interface circuit for an anti-interference miniature interface circuit used in an infrared focal plane detector according to an embodiment of this application. Detailed Implementation

[0017] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0018] This application provides an anti-interference miniature interface circuit for an infrared focal plane detector, such as... Figure 1 As shown, it mainly includes: a detector interface, a signal input conditioning circuit, a signal differential output conversion circuit, a bias voltage circuit, a timing level conversion circuit, and a miniature interface circuit, wherein: The detector interface, signal input conditioning circuit, signal differential output conversion circuit, and miniature interface circuit are connected sequentially. The detector signal is input to the signal conditioning circuit, and the detector signal is output to the miniature interface circuit through the signal differential output conversion circuit. The detector interface is used to connect the detector. In a specific example, the signal input conditioning circuit provides driving capability to the input detector signal through a low-noise source follower amplifier, and reduces high-frequency noise interference by limiting the bandwidth of the operational amplifier. A resistor network is designed at the front end of the source follower amplifier to protect the input signal from external interference fluctuations, improve the stability of signal transmission, and provide a certain degree of electrostatic absorption protection against possible electrostatic interference.

[0019] The differential output conversion circuit converts the single-ended detector signal output from the signal input conditioning circuit into two differential signals. The amplitude of the differential signals can be adjusted by the reference voltage at the other input of the differential operational amplifier, allowing the differential signal output range to match the acquisition range of the downstream ADC (signal acquisition and processing). This design achieves excellent common-mode noise suppression and reduction of total harmonic distortion, ensuring low-noise, high-quality differential output of the detector signal.

[0020] The bias voltage circuit comprises a fixed bias and an adjustable bias. The fixed bias is connected to the operating power supply, while the adjustable bias, based on a voltage reference circuit chip and an operational amplifier, provides a low-noise bias voltage for the detector interface. In this specific example, the fixed bias primarily supplies power to the detector, is externally supplied, and is output after passing through an RC filter circuit. The adjustable bias is implemented using a high-precision, low-dropout voltage reference circuit chip and an operational amplifier, and can be adjusted via the resistor value at the back end of the operational amplifier to achieve the adjustable bias function.

[0021] The timing level conversion circuit is connected between the miniature interface circuit and the detector, and is used to output the timing signal provided by the external system through the level conversion chip to the interface circuit of the detector.

[0022] In some embodiments, a constant current driving circuit for a temperature-sensing diode is further included, wherein the constant current driving circuit for a temperature-sensing diode receives a temperature measurement signal input from the detector interface and outputs it to the micro interface circuit. The constant current drive circuit for the temperature-sensing diode, implemented using resistors, diodes, and operational amplifiers, provides a stable drive current to the temperature-sensing diode inside the detector. This constant current drive circuit primarily supplies a stable drive current to the temperature-sensing diode, facilitating accurate measurement of the diode's voltage and enabling real-time, accurate monitoring of the detector's operating temperature.

[0023] This application embodiment enhances the anti-interference capability of the detector signal output through the cooperation of the signal input conditioning unit and the signal differential output conversion circuit. It effectively suppresses various interferences, including electromagnetic interference, facilitating backend signal processing and transmission. The low-noise, high-precision bias voltage circuit provides the required bias voltage and operating power for low-noise, high-precision, adjustable, and highly stable multi-channel detectors. The device is small in size, saves space through cascading, and features strong anti-interference capability and easy transmission of the detector output signal. It is highly versatile, adaptable to different types and specifications of analog signal output detectors, and easy to adjust. It offers high cost-effectiveness, ease of operation, and significant engineering value, especially for applications with high space requirements.

[0024] In some embodiments of this application, such as Figure 2 As shown, the signal input conditioning circuit includes: a differential operational amplifier N1A; The non-inverting input terminal of the differential operational amplifier is connected to the detector signal input through resistor R0, and to the VF signal input through resistor R1; The inverting input terminal of the differential operational amplifier N1A is connected to its output terminal through resistor R7.

[0025] The signal input conditioning circuit receives the signal input from the infrared focal plane detector, provides driving capability for the infrared focal plane detector signal, protects the detector signal from external interference fluctuations, and provides a certain degree of electrostatic absorption protection against possible electrostatic interference. The low-noise source amplifier (differential operational amplifier N1A) adopts the TI OPA4354 four-channel, low-noise, rail-to-rail high-speed voltage feedback CMOS operational amplifier, packaged in a small TSSOP (14) package, to buffer the two input signals of the detector. The four channels of the operational amplifier adopt completely independent circuits, which can minimize crosstalk and completely eliminate mutual interference.

[0026] In some embodiments of this application, such as Figure 3 As shown, the signal differential output conversion circuit includes: a fully differential input / output amplifier N2 and a differential operational amplifier N1B; The output signal of the differential operational amplifier N1A is connected to the first input terminal of the fully differential input / output amplifier N2 through resistor R18, and the output signal of the differential operational amplifier N1A is also connected to its first output terminal through a series connection of resistor R18 and resistor R14. The differential operational amplifier N1B has its non-inverting input terminal connected to the reference voltage through resistor R2, and its non-inverting input terminal is also connected to ground through resistor R2 and capacitor C7 in parallel. The inverting input terminal of the differential operational amplifier N1B is connected to its output terminal through resistor R8. The output terminal of the differential operational amplifier N1B is connected to the second input terminal of the fully differential input / output amplifier N2 through resistor R19. The output terminal of the differential operational amplifier N1B is connected to the second output terminal of the fully differential input / output amplifier N2 through a series connection of resistor R19 and resistor R15. The fully differential input / output amplifier N2 converts the detector signal into two differential signals through its first and second output terminals.

[0027] In a specific example, the differential output conversion circuit converts the detector signal into two differential signals. The amplitude of the differential signals can be flexibly adjusted by the reference voltage at the other input terminal of the differential operational amplifier, so that the output range of the differential signals is adapted to the acquisition range of the ADC (signal acquisition and processing) at the back end. The differential signals are sent to the external signal acquisition and processing system through a miniature external interface circuit. The differential output conversion circuit uses the TI THS4130 dual-channel, high-speed, low-noise, fully differential amplifier chip in a small VSSOP (8) package to perform differential conversion on the two input signals of the detector.

[0028] In some embodiments of this application, such as Figure 4 As shown, the fixed bias section of the bias voltage circuit is based on the series connection of a resistor and a capacitor; The adjustable bias section of the bias voltage circuit includes a voltage reference circuit chip N5 and an operational amplifier N4C. The input terminal of the voltage reference circuit chip N5 is connected to VCC, and the output terminal is connected to the non-inverting input terminal of the operational amplifier N4C through resistor R26. The output terminal of the voltage reference circuit chip N5 is grounded through the series connection of resistors R26 and R27, and the non-inverting input terminal of the operational amplifier N4C is grounded through the parallel connection of resistor R27 and capacitor C10. The inverting input terminal of the operational amplifier N4C is connected to its output terminal through capacitor C21. The output terminal of the operational amplifier N4C is connected to VP1 through resistor R13. The inverting input terminal of the operational amplifier N4C is connected to VP1 through resistor R30. VP1 is grounded through capacitor C14.

[0029] In this specific example, the fixed bias voltage of the low-noise, high-precision bias voltage circuit is 5V, supplied externally via a miniature external interface. Three channels are filtered by resistors and capacitors to remove high-frequency interference before being connected to the miniature detector interface. The adjustable bias voltage is achieved using the small-form-factor TI REF3040 high-precision, low-power, low-dropout voltage reference chip and operational amplifier. The bias voltage value can be adjusted by the resistor value at the back end of the operational amplifier, achieving adjustable bias functionality. Four adjustable bias voltages are connected to the detector via the miniature detector interface, and one adjustable bias voltage serves as the reference voltage for the other input of the differential operational amplifier.

[0030] In some embodiments of this application, such as Figure 5 As shown, the constant current drive circuit for the temperature sensing diode includes amplifier N6; The non-inverting input terminal of the amplifier N6 is connected to the positive terminal DTK of the internal temperature sensing diode of the detector, and VCC is connected to the non-inverting input terminal of the amplifier N6 through resistor R37. The output terminal of amplifier N6 outputs a measurement signal V-DTK, and the output terminal of amplifier N6 is grounded through resistors R38 and R39; The inverting input of amplifier N6 is connected between resistors R38 and R39. Specifically, DTK is the positive terminal of the internal temperature sensing diode of the detector, and DTA is the negative terminal of the internal temperature sensing diode of the detector. This application provides a stable drive current through the power supply VCC and resistor R37. At the same time, after passing through the non-inverting amplifier, it realizes accurate and stable measurement of the voltage value of the temperature sensing diode, so as to enable the external system to monitor the detector's operating temperature in real time.

[0031] In some embodiments of this application, such as Figure 6 As shown, the timing level conversion circuit includes outputting the digital signals required for the operation of the MC and INT detectors through level conversion and resistors. The timing circuit mainly involves the digital signals required for the operation of the MC and INT detectors. Since the timing signals provided by the external system are at TTL level, and the signals are susceptible to transmission interference and phenomena such as "signal overshoot", this application designs a timing level conversion circuit before the external timing signals are provided to the detectors to match the CMOS readout circuit signals of the detectors, improve the timing signal quality, and reduce interference. This circuit is responsible for converting the external system's TTL level to a more matching CMOS level for the detectors. Simultaneously, a resistor is connected to each timing signal after level conversion to filter out high-frequency interference, and then they are respectively connected to the miniature detector interface.

[0032] In some embodiments, the detector interface is a tiny rectangular connector that connects to the detector's electrical interface; the micro-interface circuit includes multiple micro-socket terminals, which respectively implement input and output according to definition.

[0033] In some embodiments of this application, such as Figure 7As shown, the miniature interface circuit is a tiny rectangular through-hole socket with a specified number of pins. For example, the X12 connector is a 16-pin tiny rectangular through-hole socket, providing a signal input / output interface for the detector. This interface is connected parallel to the interface circuit direction, with wires leading out to the detector interface via a mating connector. The X1 to X6 connectors are eight tiny gold-plated socket (female) terminals, which respectively input the power supply to the drive circuit, output the temperature sensing diode signal and the detector differential output signal, and are connected via a mating connection with a tiny socket (male) terminal for signal acquisition and processing. This interface type occupies very little space, especially in the direction perpendicular to the drive circuit, with a cascade height of less than 5mm.

[0034] This application uses a low-noise source follower amplifier and a TI THS4130 low-noise fully differential input / output amplifier chip to process the detector signal, converting the single-ended signal output of the detector into an analog differential signal output. This has the effect of suppressing various noise interferences on the detector signal, and the detector signal output has strong anti-interference ability, while improving the stability of signal transmission.

[0035] Compared with the existing technology that uses a constant current structure of DC power supply + resistor, this application designs an operational amplifier voltage regulation method, which improves the stability and reliability of the drive current, thereby improving the real-time detection accuracy and stability of the detector's operating temperature. Existing technologies use large components and connectors, requiring significant space. This application features a compact interface circuit design with miniaturized components and connectors. Miniaturization was achieved while maintaining low noise and signal accuracy. The entire interface circuit measures only 30mm × 25mm × 5mm (including assembly dimensions), fully meeting the space requirements for detector interface circuits. The interface is simple and versatile, allowing for adaptation to different types of detectors by adjusting only a portion of the bias voltage range. It also possesses mass production capability.

[0036] It should be noted that, in the embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0037] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0038] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims. All of these forms are within the protection scope of this application.

Claims

1. An anti-interference miniature interface circuit for an infrared focal plane detector, characterized in that, include: The circuit includes a detector interface, signal input conditioning circuit, signal differential output conversion circuit, bias voltage circuit, timing level conversion circuit, and miniature interface circuit, among which: The detector interface, the signal input conditioning circuit, the signal differential output conversion circuit, and the miniature interface circuit are connected in sequence. The detector signal is input to the signal conditioning circuit, and the detector signal is output to the miniature interface circuit through the signal differential output conversion circuit. The detector interface is used to connect the detector. The bias voltage circuit comprises two parts: a fixed bias voltage and an adjustable bias voltage. The fixed bias voltage is connected to the operating power supply, while the adjustable bias voltage is based on a voltage reference circuit chip and an operational amplifier, and is used to provide a low-noise bias voltage for the detector interface. The timing level conversion circuit is connected between the miniature interface circuit and the detector, and is used to output the timing signal provided by the external system through the level conversion chip to the interface circuit of the detector.

2. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 1, characterized in that, The detector interface is a tiny rectangular connector that connects to the detector's electrical interface. The micro interface circuit includes multiple micro socket terminals, which respectively realize input and output according to the definition.

3. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 1, characterized in that, It also includes a constant current driving circuit for a temperature-sensing diode, which receives the temperature measurement signal input from the detector interface and outputs it to the micro interface circuit. The constant current drive circuit for the temperature-sensing diode is implemented using resistors, diodes, and operational amplifiers, and is used to provide a stable drive current for the temperature-sensing diode inside the detector.

4. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 1, characterized in that, The signal input conditioning circuit includes: a differential operational amplifier N1A; The non-inverting input terminal of the differential operational amplifier is connected to the detector signal input through resistor R0, and to the VF signal input through resistor R1; The inverting input of the differential operational amplifier is connected to its output via resistor R7.

5. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 4, characterized in that, The signal differential output conversion circuit includes: a fully differential input / output amplifier N2 and a differential operational amplifier N1B; The output signal of the differential operational amplifier N1A is connected to the first input terminal of the fully differential input / output amplifier N2 through resistor R18, and the output signal of the differential operational amplifier N1A is also connected to its first output terminal through a series connection of resistor R18 and resistor R14. The differential operational amplifier N1B has its non-inverting input terminal connected to the reference voltage through resistor R2, and its non-inverting input terminal is also connected to ground through resistor R2 and capacitor C7 in parallel. The inverting input terminal of the differential operational amplifier N1B is connected to its output terminal through resistor R8. The output terminal of the differential operational amplifier N1B is connected to the second input terminal of the fully differential input / output amplifier N2 through resistor R19. The output terminal of the differential operational amplifier N1B is connected to the second output terminal of the fully differential input / output amplifier N2 through a series connection of resistor R19 and resistor R15. The fully differential input / output amplifier N2 converts the detector signal into two differential signals through its first and second output terminals.

6. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 5, characterized in that, The fixed bias section of the bias voltage circuit is based on a series connection of a resistor and a capacitor. The adjustable bias section of the bias voltage circuit includes a voltage reference circuit chip N5 and an operational amplifier N4C. The input terminal of the voltage reference circuit chip N5 is connected to VCC, and the output terminal is connected to the non-inverting input terminal of the operational amplifier N4C through resistor R26. The output terminal of the voltage reference circuit chip N5 is grounded through the series connection of resistors R26 and R27, and the non-inverting input terminal of the operational amplifier N4C is grounded through the parallel connection of resistor R27 and capacitor C10. The inverting input terminal of the operational amplifier N4C is connected to its output terminal through capacitor C21. The output terminal of the operational amplifier N4C is connected to VP1 through resistor R13. The inverting input terminal of the operational amplifier N4C is connected to VP1 through resistor R30. VP1 is grounded through capacitor C14.

7. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 3, characterized in that, The constant current drive circuit for the temperature-sensing diode includes amplifier N6; The non-inverting input terminal of the amplifier N6 is connected to the positive terminal DTK of the internal temperature sensing diode of the detector, and VCC is connected to the non-inverting input terminal of the amplifier N6 through resistor R37. The output terminal of amplifier N6 outputs a measurement signal V-DTK, and the output terminal of amplifier N6 is grounded through resistors R38 and R39; The inverting input of amplifier N6 is connected between resistors R38 and R39.

8. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 1, characterized in that, The timing level conversion circuit includes outputting the digital signals required for the operation of the MC and INT detectors through level conversion and resistors.

9. The anti-interference miniature interface circuit for an infrared focal plane detector as described in claim 1, characterized in that, The micro-interface circuit is a tiny rectangular through-hole socket with a specified number of pins.

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